Thin film supporting substrate for used in filter for hydrogen production filter and method for manufacturing filter for hydrogen production

ABSTRACT

In a through hole closing process, a metal plate is attached to one surface of a conductive base member having a plurality of through holes by the use of a magnet, in a copper plating process, a copper plating layer is formed on the conductive base member and the metal plate exposed within the through holes, from the side of the conductive base member where the metal plate is not attached, thereby to fill up the through holes, in a film forming process, a Pd alloy film is formed by plating on the surface of the conductive base member after removal of the metal plate, and in a removal process, the copper plating layer is removed by selective etching, thereby to produce a hydrogen production filter that is used in a reformer of a fuel cell so as to be capable of stably producing high purity hydrogen gas.

TECHNICAL FIELD

[0001] The present invention relates to a production method of ahydrogen production filter and, in particular, relates to a productionmethod of a hydrogen production filter for steam-reforming hydrocarbonfuel of various kinds to produce hydrogen rich gas for a fuel cell.

[0002] Further, the present invention relates to a thin film supportsubstrate for use in a hydrogen production filter, particularly ahydrogen production filter for steam-reforming hydrocarbon fuel ofvarious kinds to produce hydrogen rich gas for a fuel cell, and aproduction method of a hydrogen production filter using such a thin filmsupport substrate.

BACKGROUND ART

[0003] In recent years, attention has been paid to using hydrogen asfuel because there is no generation of global warming gas such as carbondioxide from the aspect of the global environmental protection and theenergy efficiency is high. Particularly, inasmuch as fuel cells candirectly convert hydrogen into electric power and enable high energyconversion efficiency in cogeneration systems utilizing generated heat,attention has been paid thereto. Heretofore, the fuel cells have beenemployed under a special condition such as in the space development orthe ocean development. Recently, however, the development has beenadvanced toward using them as automobile or household distributed powersupplies. Further, fuel cells for portable devices have also beendeveloped.

[0004] The fuel cell is a power generator wherein hydrogen rich gasobtained by reforming hydrocarbon fuel such as natural gas, gasoline,butane gas, or methanol, and oxygen in the air are reactedelectrochemically, thereby to directly produce electricity. In general,the fuel cell comprises a reformer for producing hydrogen rich gas bysteam-reforming hydrocarbon fuel, a fuel cell body for producingelectricity, a converter for converting the produced dc electricity intoalternating current, and so forth.

[0005] Depending on an electrolyte used in the fuel cell body, areaction manner, and so forth, there are five kinds in those fuel cells,i.e. a phosphoric acid fuel cell (PAFC), a molten carbonate fuel cell(MCFC), a solid oxide fuel cell (SOFC), an alkaline fuel cell (AFC), anda solid polymer fuel cell (PEFC). Among them, the solid polymer fuelcell (PEFC) has a favorable condition in that an electrolyte is solid,as compared with other fuel cells such as the phosphoric acid fuel cell(PAFC) and the alkaline fuel cell (AFC).

[0006] However, since the solid polymer fuel cell (PEFC) uses platinumas a catalyst and an operating temperature thereof is low, there is adrawback that the electrode catalyst is poisoned with a small quantityof CO, and degradation in performance is remarkable particularly in ahigh current density region. Therefore, it is necessary to produce highpurity hydrogen by reducing a concentration of CO contained in reformedgas (hydrogen rich gas) produced in a reformer, to about 10 μm.

[0007] As one of methods for removing CO from the reformed gas, therehas been used a membrane separation method employing a Pd alloy film asa filter. Unless there are pinholes, cracks, or the like in the film,the Pd alloy film can theoretically transmit only hydrogen and, bysetting the reformed gas side under high-temperature and high-pressureconditions (e.g. 300° C., 3 to 100 kg/cm²), it transmits hydrogen to thelow hydrogen partial pressure side.

[0008] In the foregoing membrane separation method, inasmuch as thetransmission speed of hydrogen is inversely proportional to a filmthickness, reduction in film thickness is required. However, in terms ofthe mechanical strength, reduction in film thickness up to about 30 μmis a limit for a Pd alloy film alone, and therefore, when a Pd alloyfilm having a thickness of about ten-odd micrometers is used, a supportmember having a porous structure is disposed on the low hydrogen partialpressure side of the Pd alloy film. However, since the Pd alloy film andthe support member are mounted in a reformer as separate members, therehas been a problem that the operability for achieving excellent sealingis bad, and durability of the Pd alloy film is not sufficient due tooccurrence of friction between the Pd alloy film and the support member.

[0009] For solving the foregoing problem, there has been developed afilter in which a Pd alloy film and a support member of a porousstructure are unified together using an adhesive. However, there hasbeen a problem that it is necessary to remove the adhesive from the Pdalloy film located at hole portions of the support member, andtherefore, the production processes are complicated. Further, since itis used under high-temperature and high-pressure conditions in thereformer, degradation of the adhesive is unavoidable, resulting ininsufficient durability of the filter.

[0010] Moreover, there is a limit to the magnitude of opening diametersof hole portions in the support member for ensuring a required strengthof the support member, and therefore, there is also a limit aboutincreasing an area of the Pd alloy film that is effective fortransmission of hydrogen, so that improvement in hydrogen transmissionefficiency has been impeded.

DISCLOSURE OF THE INVENTION

[0011] Therefore, it is an object of the present invention to provide aproduction method of a hydrogen production filter that is used in areformer of a fuel cell so as to be capable of stably producing highpurity hydrogen gas.

[0012] For accomplishing such an object, the present invention isconfigured to comprise a through hole closing step of attaching a metalplate to one surface of a conductive base member having a plurality ofthrough holes by the use of a magnet, a copper plating step of forming acopper plating layer on the conductive base member and said metal plateexposed within the through holes, from the side of said conductive basemember where said metal plate is not attached, thereby to fill up saidthrough holes, a film forming step of forming a Pd alloy film by platingon the surface of said conductive base member after removal of saidmetal plate, and a removal step of removing said copper plating layer byselective etching.

[0013] Further, the present invention is configured to comprise asticking step of sticking an insulating film to one surface of aconductive base member having a plurality of through holes, a copperplating step of forming a copper plating layer on a surface of saidconductive base member where said insulating film is not stuck, so as tofill up said through holes, a film forming step of forming a Pd alloyfilm by plating on the surface of the conductive base member afterremoval of said insulating film, and a removal step of removing saidcopper plating layer by selective etching.

[0014] Further, the present invention is configured to comprise afilling step of filling a resin material into through holes of aconductive base member having the plurality of through holes, anunderlayer forming step of forming a Pd alloy film on one surface ofsaid conductive base member by either of electroless plating and avacuum film forming method, thereby to form a conductive underlayer, afilm forming step of forming a Pd alloy film by plating on saidconductive underlayer, and a removal step of dissolving and removingonly said resin material.

[0015] Further, the present invention is configured to comprise anetching step of forming predetermined resist patterns on both surfacesof a conductive base member, and etching said conductive base memberfrom both sides using said resist patterns as masks to form a pluralityof through holes, a film forming step of forming a Pd alloy film byelectrolytic plating so as to close the inside of said through holes ofsaid conductive base member, and a removal step of removing said resistpatterns.

[0016] In the present invention as described above, even if the Pd alloyfilm is thin, since it is fixed to the conductive base member with ahigh strength so as to be unified together, durability of the filterbecomes extremely high. Therefore, according to the present invention,the Pd alloy film formed by plating is fixed to the conductive basemember having a plurality of through holes, with a high strength so asto be unified together, and no adhesive is used, and thus, it isexcellent in heat resistance and can be used under high-temperature andhigh-pressure conditions. Further, even if the Pd alloy film is reducedin thickness to increase the hydrogen transmission efficiency, it ispossible to produce a hydrogen production filter that is excellent indurability and further in operability upon mounting thereof to areformer, and so forth.

[0017] It is an object of the present invention to provide a thin filmsupport substrate enabling a hydrogen production filter that is used ina reformer of a fuel cell so as to be capable of stably producing highpurity hydrogen gas, and a production method of a hydrogen productionfilter using such a thin film support substrate.

[0018] For accomplishing such an object, the present invention isconfigured to be a thin film support substrate for use in a hydrogenproduction filter, comprising a metal substrate, a plurality of columnarconvex portions formed on one surface of said metal substrate, and aplurality of through holes formed at a portion where said columnarconvex portions are not formed, so as to pierce the metal substrate,wherein an area of the columnar convex portion non-formed portionoccupying on the columnar convex portion formed side is within the rangeof 20 to 90%.

[0019] Further, the present invention is configured to comprise, in aproduction method of a hydrogen production filer using the foregoingthin film support substrate, a disposing step of disposing an insulatingfilm on a surface of said thin film support substrate where the columnarconvex portions are formed, so as to fix the insulating film to the topsurfaces of said columnar convex portions, an underlayer forming step offorming a conductive underlayer by electroless plating on said thin filmsupport substrate excluding the top surfaces of said columnar convexportions and on a fixation side of said insulating film, a copperplating step of forming a copper plating layer on said conductiveunderlayer so as to fill up a space formed between the metal substrateof said thin film support substrate and said insulating film, and theinside of the through holes of said thin film support substrate, a filmforming step of forming a Pd alloy film by plating on a surface formedby the top surfaces of said columnar convex portions and said copperplating layer after removal of said insulating film, and a removal stepof removing said copper plating layer by selective etching.

[0020] Further, the present invention is configured to comprise, in aproduction method of a hydrogen production filer using the foregoingthin film support substrate, a disposing step of disposing an insulatingfilm on a surface of said thin film support substrate which is on anopposite side relative to a surface where the columnar convex portionsare formed, a copper platen step of forming a copper plating layer onthe surface of said thin film support substrate where the columnarconvex portions are formed, so as to fill up the inside of said throughholes and cover said columnar convex portions, a flattening step offlat-removing said copper plating layer so as to expose top surfaces ofsaid columnar convex portions and form the same flat surface with saidtop surfaces, a film forming step of forming a Pd alloy film by platingon the flat surface formed by the top surfaces of said columnar convexportions and said copper plating layer, and a removal step of removingthe copper plating layer by selective etching after removal of saidinsulating film.

[0021] Further, the present invention is configured to comprise, in aproduction method of a hydrogen production filer using the foregoingthin film support substrate, a resin layer forming step of forming aresin layer on a surface of said thin film support substrate where thecolumnar convex portions are formed, so as to fill up the inside of thethrough holes and cover said columnar convex portions, a flattening stepof flat-removing said resin layer so as to expose top surfaces of saidcolumnar convex portions and form the same flat surface with said topsurfaces, an underlayer forming step of forming a conductive underlayerby either of electroless plating and a vacuum film forming method on theflat surface formed by the top surfaces of said columnar convex portionsand said resin layer, a film forming step of forming a Pd alloy film byplating on said conductive underlayer, and a removal step of dissolvingand removing only said resin layer.

[0022] Further, the present invention is configured to comprise, in aproduction method of a hydrogen production filer using the foregoingthin film support substrate, a film forming step of forming a Pd alloyfilm by plating on one surface of a metal base member that is capable ofselective etching relative to said thin film support substrate, adiffusion joining step of disposing said metal base member on a surfaceof said thin film support substrate where the columnar convex portionsare formed, by diffusion joining said Pd alloy film to the top surfacesof the columnar convex portions, and a removal step of removing saidmetal base member by selective etching.

[0023] According to the present invention, since the thin film supportsubstrate is provided with the metal substrate, even if the area ratioof the columnar convex portion non-formed portion occupying on thecolumnar convex portion formed side is increased, the thin film supportsubstrate has a high strength, and therefore, the area of the Pd alloyfilm effective for the hydrogen transmission can be increased so thatthe hydrogen transmission efficiency can be improved. Further, in theproduction method of the present invention using such a thin filmsupport substrate of the present invention, since the Pd alloy filmformed by plating is fixed to the top surfaces of the columnar convexportions of the thin film support substrate having the through holes,with a high strength so as to be unified together, it is possible toproduce a hydrogen production filter that has a large effective hydrogentransmission area, that is excellent in heat resistance and can be usedunder high-temperature and high-pressure conditions because no adhesionis used, that is excellent in durability even if the Pd alloy film isreduced in thickness to increase the hydrogen transmission efficiency,and that is excellent in operability upon mounting thereof to areformer, and so forth.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024]FIGS. 1A to 1D are process diagrams showing one embodiment of aproduction method of a hydrogen production filter of the presentinvention.

[0025]FIGS. 2A to 2D are process diagrams showing another embodiment ofa production method of a hydrogen production filter of the presentinvention.

[0026]FIGS. 3A to 3D are process diagrams showing another embodiment ofa production method of a hydrogen production filter of the presentinvention.

[0027]FIGS. 4A to 4D are process diagrams showing another embodiment ofa production method of a hydrogen production filter of the presentinvention.

[0028]FIG. 5 is a plan view showing one embodiment of a thin filmsupport substrate of the present invention.

[0029]FIG. 6 is a longitudinal sectional view, taken along line I-I, ofthe thin film support substrate shown in FIG. 5.

[0030]FIG. 7 is a longitudinal sectional view, taken along line II-II,of the thin film support substrate shown in FIG. 5.

[0031]FIG. 8 is a longitudinal sectional view, taken along line III-III,of the thin film support substrate shown in FIG. 5.

[0032]FIGS. 9A to 9E are process diagrams showing one embodiment of aproduction method of a hydrogen production filter of the presentinvention.

[0033]FIGS. 10A to 10E are process diagrams showing another embodimentof a production method of a hydrogen production filter of the presentinvention.

[0034]FIGS. 11A to 11E are process diagrams showing another embodimentof a production method of a hydrogen production filter of the presentinvention.

[0035]FIGS. 12A to 12C are process diagrams showing another embodimentof a production method of a hydrogen production filter of the presentinvention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0036] Hereinafter, embodiments of the present invention will bedescribed.

[0037]FIGS. 1A to 1D are process diagrams showing one embodiment of aproduction method of a hydrogen production filter of the presentinvention.

[0038] In the production method of the present invention, at the outset,in a through hole closing process, a metal plate 14 is attached, by theuse of a magnet 15, to one surface 12 a of a conductive base member 12having a plurality of through holes 13, thereby to close the throughholes 13 (FIG. 1A). As a material of the conductive base member 12,there can be cited one having conductivity such as an Fe—Cr materialbeing ferrite stainless that is fixable to a magnet like SUS430, and athickness can be suitably set within the range of 20 to 500 μm,preferably 50 to 300 μm. The through holes 13 are formed by means suchas etching via a predetermined resist pattern, punching, laserprocessing, or the like. The opening size of each through hole 13 can beset within the range of 10 to 500 μm, preferably 50 to 300 μm, and thesum of opening areas of the plurality of through holes 13 relative tothe whole area of the conductive base member 12 can be set within therange of 5 to 75%, preferably 10 to 50%. Incidentally, the foregoingopening size is a diameter when an opening shape of the through hole 13is circular, while it is the mean between a maximum opening portion anda minimum opening portion when an opening shape thereof is polygonal orthe like. Hereinafter, the same shall apply in the present invention.

[0039] As the foregoing metal plate 14, there can be used one havingconductivity and being ferromagnetic or soft magnetic, and there can becited an Fe—Cr material or an Fe—C material being ferrite stainless thatis fixable to a magnet like SUS430, or an Fe—Cr—Ni material or the likethat is not fixable to a magnet like SUS304. A thickness of such a metalplate 14 can be suitably set taking into account a material thereof,magnetic charge of the using magnet 15, or the like, and can be set to,for example, about 20 to 500 μm.

[0040] As the magnet 15 that is used for attaching the metal plate 14onto the conductive base member 12, a permanent magnet, anelectromagnet, or the like in the form of a film or plate can be used.

[0041] Then, in a copper plating process, copper plating is applied to aconductive base member surface 12 b where the metal plate 14 is notattached, so as to form a copper plating layer 16 on the conductive basemember surface 12 b and on the metal plate 14 exposed in the throughholes 13, thereby filling up the through holes 13 (FIG. 1B). This copperplating process aims for filling up the through holes 13 with the copperplating, and therefore, there is no particular limitation to a thicknessand a shape of the copper plating layer 16 formed on the conductive basemember surface 12 b.

[0042] Then, in a film forming process, the foregoing metal plate 14 andmagnet 15 are removed, and a Pd alloy film 17 is formed by plating onthe conductive base member surface 12 a after the removal (FIG. 1C). Theformation of the Pd alloy film 17 can be achieved by a method in which aPd alloy film is directly formed by electrolytic plating, a method inwhich thin films of respective components composing a Pd alloy arestacked in layers on the conductive base member surface 12 a byelectrolytic plating or electroless plating, then a heat treatment isimplemented to form a Pd alloy film by diffusion of the components, orthe like. For example, by forming Pd in a thickness of 10 μm by plating,forming thereon Ag in a thickness of 1 μm by plating, then applying aheat treatment at 250° C. for 10 minutes, a Pd alloy can be obtained. Onthe other hand, a heat treatment may be implemented after carrying outmultilayer plating of three layers composed of Pd/Ag/Pd, four layerscomposed of Pd/Ag/Pd/Ag, or the like. A thickness of the Pd alloy thinfilm 17 can be set to 0.5 to 30 μm, preferably about 1 to 15 μm.

[0043] Incidentally, by applying Ni strike plating or the like to theconductive base member surface 12 a before forming the Pd alloy film 17,it is possible to increase adhesion relative to the Pd alloy film 17 tobe formed. A thickness of such Ni strike plating can be set within therange of, for example, 0.01 to 0.5 μm.

[0044] Then, in a removal process, the copper plating layer 16 isremoved by selective etching, thereby to obtain a hydrogen productionfilter 11 (FIG. 1D). The selective etching can be carried out byspraying, dipping, blowing, or the like using an ammonia etching liquid.

[0045] In the hydrogen production filter 11 thus produced, the Pd alloyfilm 17 is fixed to the conductive base member 12 with a high strength,and therefore, even if the Pd alloy film is reduced in thickness forincreasing the hydrogen transmission efficiency, it is a filter withremarkably high durability. Further, since no adhesive is used, it isexcellent in heat resistance and can be used under high-temperature andhigh-pressure conditions, and further, it is also excellent inoperability such as mounting thereof to a reformer.

[0046]FIGS. 2A to 2D are process diagrams showing another embodiment ofa production method of a hydrogen production filter of the presentinvention.

[0047] In the production method of the present invention, at the outset,in a sticking process, an insulating film 24 is stuck onto one surface22 a of a conductive base member 22 having a plurality of through holes23 (FIG. 2A). As a material of the conductive base member 22, there canbe cited austenite or ferrite stainless such as SUS304 or SUS430, or thelike, and a thickness can be suitably set within the range of 20 to 500μm, preferably 50 to 300 μm. The through holes 23 are formed by meanssuch as etching via a predetermined resist pattern, punching, laserprocessing, or the like. The opening size of each through hole 23 can beset within the range of 10 to 500 μm, preferably 50 to 300 μm, and thesum of opening areas of the plurality of through holes 23 relative tothe whole area of the conductive base member 22 can be set within therange of 5 to 75%, preferably 10 to 50%. Incidentally, the foregoingopening size is a diameter when an opening shape of the through hole 23is circular, while it is the mean between a maximum opening portion anda minimum opening portion when an opening shape thereof is polygonal orthe like. Hereinafter, the same shall apply in the present invention.

[0048] As the foregoing insulating film 24, a film of resin such aspolyethylene terephthalate, polypropylene, or polycarbonate can be used.A thickness of such an insulating film 24 can be suitably set takinginto account a material, electrical insulation performance, a filmstrength, and so forth, and can be set to, for example, about 30 to 300μm. Sticking of the insulating film 24 onto the conductive base member22 can be carried out by a method of using a polyamide or otheradhesive, a method of utilizing thermal adhesiveness of the insulatingfilm, or the like.

[0049] Then, in a copper plating process, copper plating is applied to aconductive base member surface 22 b where the insulating film 24 is notstuck, so as to form a copper plating layer 25 to thereby fill up thethrough holes 23 (FIG. 2B). This copper plating process aims for fill upthe through holes 23 with the copper plating, and therefore, there is noparticular limitation to a thickness and a shape of the copper platinglayer 25 formed on the conductive base member surface 22 b.

[0050] Then, in a film forming process, the foregoing insulating film 24is removed, and a Pd alloy film 26 is formed by plating on theconductive base member surface 22 a after the removal (FIG. 2C). Theremoval of the insulating film 24 can be carried out by peeling ordissolution. Further, the formation of the Pd alloy film 26 can beachieved by a method in which a Pd alloy film is directly formed byelectrolytic plating, a method in which thin films of respectivecomponents composing a Pd alloy are stacked in layers on the conductivebase member surface 22 a by electrolytic plating or electroless plating,then a heat treatment is implemented to form a Pd alloy film bydiffusion of the components, or the like. For example, by forming Pd ina thickness of 10 μm by plating, forming thereon Ag in a thickness of 1μm by plating, then applying a heat treatment at 900° C. for 10 hours, aPd alloy can be obtained. On the other hand, a heat treatment may beimplemented after carrying out multilayer plating of three layerscomposed of Pd/Ag/Pd, four layers composed of Pd/Ag/Pd/Ag, or the like.A thickness of the Pd alloy thin film 26 to be formed can be set to 0.5to 3 μm, preferably about 1 to 15 μm.

[0051] Incidentally, for example, by applying Ni strike plating to theconductive base member surface 22 a, it is possible to increase adhesionrelative to the Pd alloy film 26 to be formed. A thickness of such Nistrike plating can be set within the range of, for example, 0.01 to 0.1μm.

[0052] Then, in a removal process, the copper plating layer 25 isremoved by selective etching, thereby to obtain a hydrogen productionfilter 21 (FIG. 2D). The selective etching can be carried out byspraying, dipping, blowing, or the like using an ammonia etching liquid.

[0053] In the hydrogen production filter 21 thus produced, the Pd alloyfilm 26 is fixed to the conductive base member 22 with a high strength,and therefore, even if the Pd alloy film is reduced in thickness forincreasing the hydrogen transmission efficiency, it is a filter withremarkably high durability. Further, since no adhesive is used, it isexcellent in heat resistance and can be used under high-temperature andhigh-pressure conditions, and further, it is also excellent inoperability such as mounting thereof to a reformer.

[0054]FIGS. 3A to 3D are process diagrams showing another embodiment ofa production method of a hydrogen production filter of the presentinvention.

[0055] First, in a filling process, a resin material 34 is filled in aplurality of through holes 33 provided in a conductive base member 32(FIG. 3A). A material and a thickness of the conductive base member 32can be the same as those of the foregoing conductive base member 22, anda forming method, dimensions, and a formation density of the throughholes 33 can also be the same as those of the foregoing through holes23. Further, the conductive base member 32 may be applied with, forexample, Ni strike plating after the formation of the through holes 33,thereby to increase adhesion relative to a Pd alloy film formed in asubsequent process. A thickness of such Ni strike plating can be setwithin the range of, for example, 0.01 to 1.0 μm.

[0056] The foregoing resin material can exhibit stable resistance inlater-described underlayer forming process and film forming process andcan be surely dissolved/removed in a removal process and, for example,novolak resist resin or the like can be used therefor. For filling sucha resin material into the through holes 33, a method such as squeezingor the like can be employed.

[0057] Then, in the underlayer forming process, a Pd alloy film isformed on one surface of the conductive base member 32 in which theresin material 34 is filled in the through holes 33, thereby to form aconductive underlayer 35 (FIG. 3B). This underlayer forming process aimsfor giving conductivity to exposed surfaces of the resin material 34filled in the through holes 33, and a thickness of the conductiveunderlayer 35 to be formed can be set within the range of 0.01 to 0.2μm. The Pd alloy film to be the conductive underlayer 35 can be formedby electroless plating, or may be formed by a vacuum film forming methodsuch as sputtering or vacuum deposition.

[0058] Then, in the film forming process, a Pd alloy film 36 is formedon the conductive underlayer 35 by plating (FIG. 3C). The formation ofthis Pd alloy film 36 can be achieved by a method in which a Pd alloyfilm is directly formed by electrolytic plating, a method in which thinfilms of respective components composing a Pd alloy are stacked inlayers on the conductive underlayer 35 by electrolytic plating orelectroless plating, then a heat treatment is implemented to form a Pdalloy film by diffusion of the components, or the like. A thickness ofthe Pd alloy thin film 36 to be formed can be set to 0.5 to 30 μm,preferably about 1 to 15 μm.

[0059] Then, in the removal process, only the resin material 34 isdissolved to be removed, thereby to obtain a hydrogen production filter31 (FIG. 3D). The dissolution/removal of the resin material 34 can becarried out by spraying, dipping, or the like using a solvent such asacetone, methyl ethyl ketone, methyl isobutyl ketone, or the like, adesmear solution (manufactured by Shipley Corporation), or the likedepending on the resin material to be used.

[0060] In the hydrogen production filter 31 thus produced, the Pd alloyfilm 36 is fixed to the conductive base member 32 with a high strengthvia the conductive underlayer 35, and therefore, even if the Pd alloyfilm is reduced in thickness for increasing the hydrogen transmissionefficiency, it is a filter with remarkably high durability. Further,since no adhesive is used, it is excellent in heat resistance and can beused under high-temperature and high-pressure conditions, and further,it is also excellent in operability such as mounting thereof to areformer.

[0061]FIGS. 4A to 4D are process diagrams showing another embodiment ofa production method of a hydrogen production filter of the presentinvention.

[0062] In the production method of the present invention, in an etchingprocess, at the outset, resist patterns 44 a and 44 b having a pluralityof small opening portions are formed on both surfaces of a conductivebase member 42 (FIG. 4A). The small opening portions of the resistpattern 44 a confront the small opening portions of the resist pattern44 b, respectively, via the conductive base member 42, and opening areasof the mutually confronting small opening portions may be equal to eachother, or one of them, for example, the opening area of the smallopening portion of the resist pattern 44 b, may be set greater. Theshapes and sizes of the small opening portions of such resist patterns44 a and 44 b can be suitably set taking into account an etchingcondition, a material and a thickness of the conductive base member 42,and so forth. The material and thickness of the conductive base member42 can be the same as those of the foregoing conductive base member 22.Further, the resist patterns 44 a and 44 b can be each formed byapplying a material selected from conventionally known positive andnegative photosensitive resist materials, exposing it via apredetermined mask, and developing it.

[0063] Then, by etching the conductive base member 42 using theforegoing resist patterns 44 a and 44 b as masks, a plurality of finethrough holes 43 are formed in the conductive base member 42 (FIG. 4B).The etching of the conductive base member 42 can be carried out byspraying, dipping, blowing, or the like by the use of an etching liquidof iron chloride, copper chloride, or the like. The opening size on theside of a conductive base member surface 42 a and the opening size onthe side of a conductive base member surface 42 b, of each through hole43 formed in the conductive base member 42 by the etching can be setwithin the range of 10 to 500 μm, preferably 50 to 300 μm, and the sumof opening areas of the plurality of through holes 43 relative to thewhole area of the conductive base member 42 can be set within the rangeof 5 to 75%, preferably 10 to 50%. Incidentally, upon etching theconductive base member 42 from both surfaces using the resist patterns44 a and 44 b as masks, a projected portion 43 a is generally formed ata substantially central portion of an inner wall surface of each formedthrough hole 43. Therefore, when such a projected portion 43 a exists,the foregoing opening area of the through hole 43 is an opening area atthe projected portion 43 a.

[0064] Then, in a film forming process, Pd alloy films 46 are formed byelectrolytic plating so as to close the inside of the through holes 43of the conductive base member 42 (FIG. 4C). The formation of the Pdalloy films 46 can be achieved, using the resist patterns 44 a and 44 bas masks, according to a method in which Pd alloy films are directlyformed by electrolytic plating, a method in which thin films ofrespective components composing a Pd alloy are formed by electrolyticplating, then a heat treatment is implemented to form Pd alloy films bydiffusion of the components, or the like. In the formation of such a Pdalloy film 46, when the projected portion 43 a exists at thesubstantially central portion of the inner wall surface of the throughhole 43 formed in the foregoing etching process, the current densityincreases at the projected portion 43 a so that the Pd alloy film isformed so as to close the projected portion 43 a. A thickness of the Pdalloy thin film 46 to be formed can be set to 0.5 to 30 μm, preferablyabout 1 to 15 μm. Further, by applying Ni strike plating to the insideof the through holes 43 of the conductive base member 42 before formingthe foregoing Pd alloy films, it is possible to increase adhesionrelative to the Pd alloy films. A thickness of such Ni strike platingcan be set within the range of, for example, 0.01 to 0.1 μm.

[0065] Then, in a removal process, the resist patterns 44 a and 44 b areremoved to thereby obtain a hydrogen production filter 41 (FIG. 4D). Theremoval of the resist patterns 44 a and 44 b can be carried out using asodium hydroxide solution or the like.

[0066] In the hydrogen production filter 41 thus produced, the Pd alloyfilms 46 are fixed to the conductive base member 42 with a high strengthso as to close the through holes 43, and therefore, even if the Pd alloyfilms are reduced in thickness for increasing the hydrogen transmissionefficiency, it is a filter with remarkably high durability. Further,since no adhesive is used, it is excellent in heat resistance and can beused under high-temperature and high-pressure conditions, and further,it is also excellent in operability such as mounting thereof to areformer.

[0067]FIG. 5 is a plan view showing one embodiment of a thin filmsupport substrate of the present invention, FIG. 6 is a longitudinalsectional view, taken along line I-I, of the thin film support substrateshown in FIG. 5, FIG. 7 is a longitudinal sectional view, taken alongline II-II, of the thin film support substrate shown in FIG. 5, and FIG.8 is a longitudinal sectional view, taken along line III-III, of thethin film support substrate shown in FIG. 5. In FIGS. 5 to 8, a thinfilm support substrate 51 comprises a metal substrate 52, a plurality ofcolumnar convex portions 53 formed in predetermined positions of onesurface of the metal substrate 52, and a plurality of through holes 54formed in predetermined positions of a portion 52 a where the columnarconvex portions 53 are not formed, so as to pierce the metal substrate52. An occupying area of the columnar convex portion non-formed portion52 a on the side where the columnar convex portions 53 are formed, iswithin the range of 20 to 90%, preferably 30 to 85%. When the area ofthe columnar convex portion non-formed portion 52 a is less than 20%, aneffect of increasing an area of a Pd alloy film effective for thehydrogen transmission does not become sufficient, while, when it exceeds90%, supporting of the hydrogen transmission film is impeded to lowerdurability of a hydrogen production filer, which is not preferable.

[0068] A material of the metal substrate 52 forming the thin filmsupport substrate 51 may be, for example, austenite or ferrite stainlesssuch as SUS304 or SUS430. A thickness of the metal substrate 52 (athickness at the columnar convex portion non-formed portion 52 a) can besuitably set within the range of 20 to 300 μm. If the thickness of themetal substrate 52 is less than 20 μm, the strength of the thin filmsupport substrate 51 becomes insufficient, while, if it exceeds 300 μm,there occurs an evil influence of increase in weight, and it becomesdifficult to form the through holes 54, which is not preferable.

[0069] Diameters of the columnar convex portions 53 forming the thinfilm support substrate 51 can be each set within the range of 20 to 500μm, preferably 30 to 300 μm, and the formation pitch thereof can be setwithin the range of 40 to 700 μm, preferably 60 to 520 μm, thereby toset the area of the columnar convex portion non-formed portion 52 a tooccupy 20 to 90% as described above. Further, a height of each columnarconvex portion 53 can be set within the range of 10 to 200 μm,preferably 20 to 150 μm. The columnar convex portion has a cylindricalshape in the shown example, but is not limited thereto. Such columnarconvex portions 53 can be formed by, for example, half-etching the metalsubstrate from one surface via a resist pattern having a plurality ofrequired opening portions.

[0070] An opening diameter of each through hole 54 forming the thin filmsupport substrate 51 can be set within the range of 20 to 200 μm,preferably 50 to 150 μm. On the other hand, if inner diameters of thethrough hole 54 are not uniform, the minimum inner diameter is set to bethe opening diameter. The thin film support substrate 51 of the presentinvention is formed with a Pd alloy film on top surfaces 53 a of thecolumnar convex portions 53 to thereby constitute a hydrogen productionfilter, and the side of the through holes 54 become the low hydrogenpartial pressure side. Therefore, the formation density of the throughholes 54 is sufficient as long as it is within a range not giving aninfluence on the strength of the metal substrate 52. For example, aratio of A/B per unit area between the number A of the columnar convexportions 53 and the number B of the through holes 54 can be set to about1 to 10. Such through holes 54 can be formed by, for example, etchingthe metal substrate 52 from both surfaces via resist patterns eachhaving a plurality of required opening portions.

[0071] In the shown example, the columnar convex portions 53 and thethrough holes 54 are formed such that a triangle having as its vertexesthe centers of the nearest three columnar convex portions 53 forms aregular triangle, a triangle having as its vertexes the centers of thenearest three through holes 54 forms a regular triangle, and the vertexof one of the regular triangles is located in a position of the centerof gravity of the other regular triangle, however, not limited thereto.

[0072] Since the foregoing thin film support substrate 51 of the presentinvention is provided with the metal substrate 52, even if the arearatio of the columnar convex portion non-formed portion 52 a occupyingon the side where the columnar convex portions 53 are formed isincreased, the required strength can be maintained, and therefore, thearea of the Pd alloy film effective for the hydrogen transmission can beincreased.

[0073] Now, description will be given about a production method of ahydrogen production filter of the present invention using the thin filmsupport substrate of the present invention.

[0074]FIGS. 9A to 9E are process diagrams showing one embodiment of aproduction method of a hydrogen production filter of the presentinvention using the foregoing thin film support substrate 51.

[0075] In the production method of the present invention, at the outset,in a disposing process, an insulating film 62 is disposed on the surfaceof the thin film support substrate 51 where the columnar convex portions53 are formed, so as to be fixed to the top surfaces 53 a of thecolumnar convex portions 53 (FIG. 9A). As the insulating film 62, forexample, a film of resin such as polyethylene terephthalate,polypropylene, or polycarbonate can be used. A thickness of such aninsulating film 62 can be suitably set taking into account a material,electrical insulation performance, a film strength, and so forth, andcan be set to, for example, about 30 to 300 μm. Fixation of theinsulating film 62 onto the top surfaces 53 a of the columnar convexportions 53 can be carried out by, for example, a method of using apolyamide or other adhesive, a method of utilizing thermal adhesivenessof the insulating film, or the like. On the other hand, as theinsulating film, a dry film resist may be disposed. By using the dryfilm resist, later-described removal of the insulating film 62 can becarried out using a peeling liquid such as an alkaline aqueous solutionand, as compared with the case of using the foregoing resin film, it isadvantageous that there is no physical damage to the thin film supportsubstrate 51. When a photosensitive dry film resist is used as theinsulating film, fixation onto the top surfaces 53 a of the columnarconvex portions 53 can be carried out by a method wherein the wholesurface is exposed after roll laminating or vacuum laminating and, ifnecessary, hot curing is implemented, or the like.

[0076] Then, in an underlayer forming process, a conductive underlayer63 is formed by electroless plating on the thin film support substrate51 excluding the top surfaces 53 a of the columnar convex portions 53(including the inside of the through holes 54), and on the fixation sideof the insulating film 62 (FIG. 9B). The formation of this conductiveunderlayer 63 can be performed by electroless nickel plating,electroless copper plating, or the like, and a thickness of theconductive underlayer 63 can be set within the range of about 0.01 to0.2 μm. The condition of this electroless plating is suitably setdepending on a material of the insulating film 62 to be used.

[0077] Then, in a copper plating process, a copper plating layer 64 isformed on the conductive underlayer 63 so as to fill up spaces formedbetween the metal substrate 52 of the thin film support substrate 51 andthe insulating film 62, and the inside of the through holes 54 of thethin film support substrate 51 (FIG. 9C).

[0078] Then, in a film forming process, the insulating film 62 isremoved, and thereafter, a Pd alloy film 65 is formed by plating on asurface formed by the top surfaces 53 a of the columnar convex portions53 and the copper plating layer 64 (conductive underlayer 63) (FIG. 9D).The removal of the insulating film 62 can be carried out by peeling ordissolution. Further, the formation of the Pd alloy film 65 can beachieved by a method in which a Pd alloy film is directly formed byelectrolytic plating, a method in which thin films of respectivecomponents composing a Pd alloy are stacked in layers by electrolyticplating or electroless plating, then a heat treatment is implemented toform a Pd alloy film by diffusion of the components, or the like. Forexample, by forming Pd in a thickness of 10 μm by plating, formingthereon Ag in a thickness of 1 μm by plating, then applying a heattreatment at 250° C. for 10 minutes, a Pd alloy can be obtained. On theother hand, a heat treatment may be implemented after carrying outmultilayer plating of three layers composed of Pd/Ag/Pd, four layerscomposed of Pd/Ag/Pd/Ag, or the like. A thickness of the Pd alloy thinfilm 65 to be formed can be set to 0.5 to 30 μm, preferably about 1 to15 μm.

[0079] Then, in a removal process, the copper plating layer 64(conductive underlayer 63) is removed by selective etching, thereby toobtain a hydrogen production filter 61 (FIG. 9E). The selective etchingcan be carried out by spraying, dipping, blowing, or the like using anammonia etching liquid.

[0080]FIGS. 10A to 10E are process diagrams showing another embodimentof a production method of a hydrogen production filter of the presentinvention.

[0081] First, in a disposing process, an insulating film 72 is disposedon the surface of the thin film support substrate 51, which is on theopposite side relative to the surface where the columnar convex portions53 are formed (FIG. 10A). As the insulating film 72, one that is thesame as the foregoing insulating film 62 can be used, and a disposingmethod of the insulating film 72 can be the same as that of theforegoing insulating film 62.

[0082] Then, in a copper plating process, a copper plating layer 74 isformed on the surface of the thin film support substrate 51 where thecolumnar convex portions 53 are formed, so as to fill up the inside ofthe through holes 54 and cover the columnar convex portions 53 (FIG.10B).

[0083] Then, in a flattening process, the copper plating layer 74 isflat-removed so as to expose the top surfaces 53 a of the columnarconvex portions 53 and form the same flat surface with the top surfaces53 a (FIG. 10C). The flat removal of the copper plating layer 74 can becarried out by, for example, mechanical grinding or the like.

[0084] Then, in a film forming process, a Pd alloy film 75 is formed byplating on the flat surface formed by the top surfaces 53 a of thecolumnar convex portions 53 and the copper plating layer 74 (FIG. 10D).The formation of this Pd alloy film 75 can be performed like theformation of the foregoing Pd alloy film 65.

[0085] Then, in a removal process, the insulating film 72 is removed,and thereafter, the copper plating layer 74 is removed by selectiveetching, thereby to obtain a hydrogen production filter 71 (FIG. 10E).The removal of the insulating film 72 can be carried out like theremoval of the foregoing insulating film 62. Further, the removal of thecopper plating layer 74 can also be carried out like the removal of theforegoing copper plating layer 64.

[0086] In the foregoing example, the insulating film 72 is removed inthe removal process. However, it may also be configured that theinsulating film 72 is removed before the flattening process and, afterthe flattening process, the insulating film 72 is again disposed, beforethe film forming process, on the surface of the thin film supportsubstrate 51 which is on the opposite side relative to the surface wherethe columnar convex portions 53 are formed, and then removed in theremoval process.

[0087]FIGS. 11A to 11E are process diagrams showing another embodimentof a production method of a hydrogen production filter of the presentinvention.

[0088] First, in a resin layer forming process, a resin layer 82 isformed on the surface of the thin film support substrate 51 where thecolumnar convex portions 53 are formed, so as to fill up the inside ofthe through holes 54 and cover the columnar convex portions 53 (FIG.11A). The resin layer 82 can be formed by, for example, pouring amonomer solution of thermosetting resin such as epoxy resin,bismaleimide resin, or phenol resin by squeezing or the like, and hotcuring it at a predetermined curing temperature.

[0089] Then, in a flattening process, the resin layer 82 is flat-removedso as to expose the top surfaces 53 a of the columnar convex portions 53and form the same flat surface with the top surfaces 53 a (FIG. 11B).The flat removal of the resin layer 82 can be carried out by, forexample, mechanical grinding or the like.

[0090] Then, in an underlayer forming process, a conductive underlayer83 is formed on the flat surface formed by the tope surfaces 53 a of thecolumnar convex portions 53 and the resin layer 82, by eitherelectroless plating or a vacuum film forming method (FIG. 1C). Whenforming the conductive underlayer 83 by electroless plating, it can becarried out by electroless nickel plating, electroless copper plating,or the like, and a thickness of the conductive underlayer 83 can be setwithin the range of about 0.01 to 0.2 μm. The condition of thiselectroless plating is suitably set depending on a material of the resinlayer 82. On the other hand, when forming the conductive underlayer 83by the vacuum film forming method, a thin film of Ni, Cu, Ag, Pd, or thelike can be formed, and a thickness of this thin film can be set withinthe range of about 0.01 to 0.2 μm.

[0091] Then, in a film forming process, a Pd alloy film 85 is formed byplating on the conductive underlayer 83 (FIG. 1D). The formation of thisPd alloy film 85 can be implemented like the formation of the foregoingPd alloy film 65.

[0092] Then, in a removal process, only the resin layer 82 is dissolvedto be removed, thereby to obtain a hydrogen production filter 81 (FIG.11E). The removal of the resin layer 82 can be carried out using anorganic solvent or the like that can dissolve the resin layer 82. In theremoval of the resin layer 82, the conductive underlayer 83 is removedso as to expose a surface of the Pd alloy film 85 on the side of thethin film support substrate 51. The removal of the conductive underlayer83 can be implemented by a hydrogen peroxide/sulfuric acid etchingliquid when Ni is used, and by an ammonia alkaline etching liquid whenCu is used. When Ag is used, since it can be formed into an alloy withPd due to heat diffusion, removal thereof is not necessary.

[0093]FIGS. 12A to 12C are process diagrams showing another embodimentof a production method of a hydrogen production filter of the presentinvention.

[0094] First, in a film forming process, a Pd alloy film 95 is formed byplating on one surface of a metal base member 92 that is capable ofselective etching relative to the thin film support substrate 51 (FIG.12A). As the foregoing metal base member 92, copper, a copper alloy, orthe like can be used, and a thickness can be suitably set within therange of 0.05 to 0.3 mm. The formation of the Pd alloy film 95 can becarried out like the formation of the foregoing Pd alloy film 65.Incidentally, for example, by applying Ni strike plating to the metalbase member 92, it is possible to increase adhesion relative to the Pdalloy film 95 to be formed. A thickness of such Ni strike plating can beset within the range of, for example, 0.01 to 1.0 μm.

[0095] Then, in a diffusion joining process, the metal base member 92 isdisposed on the surface of the thin film support substrate 51 where thecolumnar convex portions 53 are formed, by diffusion joining theforegoing Pd alloy film 95 to the top surfaces 53 a of the columnarconvex portions 53 (FIG. 12B). The joining between the Pd alloy film 95and the top surfaces 53 a of the columnar convex portions 53 bydiffusion joining can be carried out by applying a heat treatment at 900to 1400° C. for 12 to 18 hours in a vacuum.

[0096] Then, in a removal process, the metal base member 92 is removedby selective etching, thereby to obtain a hydrogen production filter 91(FIG. 12C). When, for example, the metal base member 92 is a copper basemember, the selective etching can be carried out by spraying, dipping,blowing, or the like using an ammonia etching liquid.

[0097] Since any of the hydrogen production filters 61, 71, 81, and 91produced as described above uses the thin film support substrate 51 ofthe present invention, the area of the Pd alloy film effective for thehydrogen transmission is large, and the Pd alloy film is fixed, with ahigh strength, to the columnar convex portions 53 of the thin filmsupport substrate 51 having a high strength. Therefore, even if the Pdalloy film is reduced in thickness for increasing the hydrogentransmission efficiency, it is a filter with remarkably high durability.Further, since no adhesive is used, it is excellent in heat resistanceand can be used under high-temperature and high-pressure conditions, andfurther, it is also excellent in operability such as mounting thereof toa reformer.

[0098] Now, the present invention will be described in further detailshowing more specific examples.

EXAMPLE 1 Production of Filter for Hydrogen Production

[0099] A SUS430 member having a thickness of 50 μm was prepared as abase member, and a photosensitive resist material (OFPR manufactured byTokyo Ohka Kogyo Co., Ltd.) was applied (film thickness: 7 μm (upondrying)) to both surfaces of the SUS430 member by a dip method. Then,photomasks each having, in a pitch of 200 μm, a plurality of circularopening portions each having an opening size (opening diameter) of 120μm were disposed on the foregoing resist application films, and theresist application films were exposed via the photomasks and developedusing a sodium hydrogen carbonate solution. By this, resist patternshaving the circular opening portions with the opening size (openingdiameter) of 120 μm were formed on both surfaces of the SUS430 member.Incidentally, the centers of the respective opening portions of theresist patterns formed on the surfaces were set to coincide with eachother via the SUS430 member.

[0100] Then, the SUS430 member was etched under the following conditionusing the foregoing resist patterns as masks.

[0101] <Etching Condition>

[0102] Temperature: 50° C.

[0103] Iron chloride concentration: 45 Baume

[0104] Pressure: 3 kg/cm²

[0105] After the foregoing etching process was finished, the resistpatterns were removed using a sodium hydroxide solution, and washing inwater was carried out. By this, a conductive base member was obtainedwherein a plurality of circular through holes were formed in the SUS430member. The formed through holes each had a projected portion at asubstantially central portion of an inner wall surface, and an openingsize (opening diameter) at the projected portion was 70 μm.

[0106] Then, a metal plate (SUS430 member) having a thickness of 200 μmwas attached to one surface of the foregoing SUS430 member by the use ofa plate permanent magnet to thereby close the through holes.(hereinabove, the through hole closing process)

[0107] Then, electrolytic copper plating was carried out under thefollowing condition relative to a surface of the SUS430 member where themetal plate was not attached, so as to form a copper plating layer onthe surface of the SUS430 member and on the metal plate exposed withinthe through holes, thereby filling up the through holes with the copperplating. A thickness of the copper plating layer on the surface of theSUS430 member was set to 80 μm. (hereinabove, the copper platingprocess)

[0108] <Copper Plating Condition>

[0109] Copper sulfate plating bath

[0110] Liquid temperature: 30° C.

[0111] Current density: 1 A/dm²

[0112] Then, the metal plate and the plate permanent magnet were removedfrom the SUS430 member, and a Pd alloy film (thickness: 8 μm) was formedby electrolytic plating on the surface of the SUS430 member after theremoval under the following condition. (hereinabove, the film formingprocess)

[0113] <Film Forming Condition of Pd Alloy Film by Electrolytic Plating>

[0114] Pd chloride plating bath

[0115] Temperature: 40° C.

[0116] Current density: 1 A/dm²

[0117] Then, the copper plating layer was removed by selective etching.(hereinabove, the removal process) After the foregoing removal of thecopper plating layer was finished, cutting into a size of 3 cm×3 cm wascarried out to obtain a filter for hydrogen production.

Evaluation of Hydrogen Production Filter

[0118] The hydrogen production filter thus produced was mounted in areformer, and a mixture of butane gas and steam was continuouslysupplied to the Pd alloy film of the filter under high-temperature andhigh-pressure conditions (300° C., 10 kg/cm²), thereby to measure COconcentrations and flow rates of hydrogen rich gas transmitted to theside of the porous base member of the filter. As a result, the COconcentrations immediately after the start of reforming up to a lapse of300 hours were 8 to 10 μm which were extremely low, and the flow ratesof the hydrogen rich gas were 10 L/hour, and therefore, it was confirmedthat the hydrogen production filter produced by the present inventionwas excellent in durability and hydrogen transmission efficiency.

COMPARATIVE EXAMPLE 1 Production of Filter for Hydrogen Production

[0119] Like in Example 1, a conductive base member was obtained byforming a plurality of through holes in a SUS430 member. Then, a Pdalloy film having a thickness of 30 μm was bonded to the conductive basemember via an adhesive so as to be unified together, and thereafter, theadhesive remaining in the through holes of the conductive base memberwas removed using acetone. This unified composite was cut into a size of3 cm×3 cm to obtain a filter for hydrogen production.

Evaluation of Hydrogen Production Filter

[0120] The filter thus produced was mounted in a reformer, and a mixtureof butane gas and steam was supplied to the Pd alloy film of the filterunder the same condition as Example 1, thereby to measure COconcentrations and flow rates of hydrogen rich gas transmitted to theside of the porous base member of the filter. As a result, the COconcentrations were 8 to 10 μm, which were extremely low and thusexcellent, immediately after the start of reforming up to a lapse of 300hours. However, after the lapse of 300 hours, peeling of the Pd alloyfilm was caused due to degradation of the adhesive underhigh-temperature and high-pressure conditions, and the CO concentrationwas increased to about 3% due to generation of cracks of the Pd alloyfilm or the like, and therefore, it was confirmed that durability wasbad.

EXAMPLE 2 Production of Filter for Hydrogen Production

[0121] A SUS304 member having a thickness of 50 μm was prepared as abase member, and a photosensitive resist material (OFPR manufactured byTokyo Ohka Kogyo Co., Ltd.) was applied (film thickness: 7 μm (upondrying)) to both surfaces of the SUS304 member by a dip method. Then,photomasks each having, in a pitch of 200 μm, a plurality of circularopening portions each having an opening size (opening diameter) of 120μm were disposed on the foregoing resist application films, and theresist application films were exposed via the photomasks and developedusing a sodium hydrogen carbonate solution. By this, resist patternshaving the circular opening portions with the opening size (openingdiameter) of 120 μm were formed on both surfaces of the SUS304 member.Incidentally, the centers of the respective opening portions of theresist patterns formed on the surfaces were set to coincide with eachother via the SUS304 member.

[0122] Then, the SUS304 member was etched under the following conditionusing the foregoing resist patterns as masks.

[0123] <Etching Condition>

[0124] Temperature: 50° C.

[0125] Iron chloride concentration: 45 Baume

[0126] Pressure: 3 kg/cm²

[0127] After the foregoing etching process was finished, the resistpatterns were removed using a sodium hydroxide solution, and washing inwater was carried out. By this, a conductive base member was obtainedwherein a plurality of through holes were formed in the SUS304 member.The formed through holes each had a projected portion at a substantiallycentral portion of an inner wall surface, and an opening size (openingdiameter) at the projected portion was 70 μm.

[0128] Then, an insulating film having a thickness of 200 μm was stuckto one surface of the foregoing SUS304 member. (hereinabove, thesticking process)

[0129] Then, electrolytic copper plating was carried out under thefollowing condition relative to a surface of the SUS304 member where theinsulating film was not stuck, so as to fill up the through holes withthe copper plating and form a copper plating layer (thickness: about 80μm) on the surface of the SUS304 member. (hereinabove, the copperplating process)

[0130] <Copper Plating Condition>

[0131] Using bath: Copper sulfate plating bath

[0132] Liquid temperature: 30° C.

[0133] Current density: 1 A/dm²

[0134] Then, the insulating film was peeled and removed from the SUS304member, and a Pd alloy film (thickness: 8 μm) was formed by electrolyticplating on the surface of the SUS304 member after the removal under thefollowing condition. (hereinabove, the film forming process)

[0135] <Film Forming Condition of Pd Alloy Film by Electrolytic Plating>

[0136] Using bath: Pd chloride plating bath (Pd concentration: 12 g/L)

[0137] pH: 7 to 8

[0138] Current density: 1 A/dm²

[0139] Liquid temperature: 40° C.

[0140] Then, the copper plating layer was removed by selective etching.(hereinabove, the removal process)

[0141] After the foregoing removal of the copper plating layer wasfinished, cutting into a size of 3 cm×3 cm was carried out to obtain afilter for hydrogen production.

Evaluation of Hydrogen Production Filter

[0142] The hydrogen production filter thus produced was mounted in areformer, and a mixture of butane gas and steam was supplied to the Pdalloy film of the filter under the same condition as Example 1, therebyto measure CO concentrations and flow rates of hydrogen rich gastransmitted to the side of the porous base member of the filter. As aresult, the CO concentrations immediately after the start of reformingup to a lapse of 300 hours were 8 to 10 μm which were extremely low, andthe flow rates of the hydrogen rich gas were 10 L/hour, and therefore,it was confirmed that the hydrogen production filter produced by thepresent invention was excellent in durability and hydrogen transmissionefficiency.

EXAMPLE 3 Production of Filter for Hydrogen Production

[0143] Like in Example 2, a conductive base member was obtained byforming a plurality of through holes in a SUS304 member.

[0144] Then, Ni strike plating (thickness: 0.01 μm) was applied to theforegoing SUS304 member under the following condition, and thereafter, aresin material (AZ111 manufactured by Shipley Corporation) were filledin the through holes of the foregoing SUS304 member. The filling of theresin material was performed by squeezing. (hereinabove, the fillingprocess)

[0145] <Ni Strike Plating Condition> Bath composition: Nickel chloride300 g/L Boric acid  30 g/L pH: 2 Liquid temperature: 55 to 65° C.Current density: 10 A/dm²

[0146] Then, the following pretreatment was applied to one surface ofthe SUS304 member in which the resin material was filled in the throughholes, and thereafter, electroless plating was carried out under thefollowing condition to form an electroless Ni plating layer (thickness:0.4 μm) on the surfaces of the resin material filled in the throughholes and on the surface of the SUS304 member, thereby to obtain aconductive underlayer. (hereinabove, the underlayer forming process)

[0147] <Pretreatment>

[0148] alkaline degreasing→washing in water→chemical etching (inammonium persulfate 200 g/L aqueous solution (20° C.±5° C.))→washing inwater→acid treatment (10% dilute sulfuric acid (ordinarytemperature))→washing in water→acid treatment (30% dilute hydrochloricacid (ordinary temperature))→dipping in sensitizer added liquid(composition: 0.5 g of Pd chloride, 25 g of stannous chloride, 300 μmLof hydrochloric acid, 600 μmL of water)→washing in water

[0149] <Electroless Ni Plating Condition> Bath composition: Ni sulfate20 g/L Sodium hypophosphite 10 g/L Lactic acid  3 g/L Sodium citrate  5g/L Sodium acetate  5 g/L pH: 4.5 to 6.0 Liquid temperature: 50 to 65°C.

[0150] Then, a Pd alloy film (thickness: 8 μm) was formed byelectrolytic plating on the foregoing conductive underlayer under thefollowing condition. (hereinabove, the film forming process)

[0151] <Film Forming Condition of Pd Alloy Film by Electrolytic Plating>

[0152] Using bath: Pd chloride plating bath (Pd concentration: 12 g/L)

[0153] pH: 7 to 8

[0154] Current density: 1 A/dm²

[0155] Liquid temperature: 40° C.

[0156] Then, the resin material filled in the through holes wasdissolved to be removed using the following treatment bath (Desmear Bathmanufactured by Shipley Corporation). (hereinabove, the removal process)

[0157] <Treatment Condition of Desmear Bath> Bath composition MLB-211 20vol % of swelling process: Cup-Z 10 vol % Bath temperature 80° C. ofswelling process: Bath composition of MLB-213A 10 vol % rougheningprocess: MLB-213B 15 vol % Bath temperature of 80° C. rougheningprocess:

[0158] After the foregoing removal of the resin material was finished,cutting into a size of 3 cm×3 cm was carried out to obtain a filter forhydrogen production.

Evaluation of Hydrogen Production Filter

[0159] The filter thus produced was mounted in a reformer, and a mixtureof butane gas and steam was supplied to the Pd alloy film of the filterunder the same condition as Example 1, thereby to measure COconcentrations and flow rates of hydrogen rich gas transmitted to theside of the porous base member of the filter. As a result, the COconcentrations immediately after the start of reforming up to a lapse of300 hours were 8 to 10 μm which were extremely low, and the flow ratesof the hydrogen rich gas were 10 L/hour, and therefore, it was confirmedthat the hydrogen production filter produced by the present inventionwas excellent in durability and hydrogen transmission efficiency.

EXAMPLE 4 Production of Filter for Hydrogen Production

[0160] A filter for hydrogen production was produced like in Example 3except that a Pd alloy film (thickness: 0.2 μm) was formed by asputtering method under the following condition instead of theelectroless plating method in the underlayer forming process, thereby toobtain a conductive underlayer.

[0161] <Sputtering Condition>

[0162] RF power: 500 W

[0163] Argon gas pressure: 5.4×10⁻²Pa

[0164] dc current: 2.5 A

Evaluation of Hydrogen Production Filter

[0165] The filter thus produced was mounted in a reformer, and a mixtureof butane gas and steam was supplied to the Pd alloy film of the filterunder the same condition as Example 1, thereby to measure COconcentrations and flow rates of hydrogen rich gas transmitted to theside of the porous base member of the filter. As a result, the COconcentrations immediately after the start of reforming up to a lapse of300 hours were 8 to 10 ppm which were extremely low, and the flow ratesof the hydrogen rich gas were 10 L/hour, and therefore, it was confirmedthat the hydrogen production filter produced by the present inventionwas excellent in durability and hydrogen transmission efficiency.

EXAMPLE 5 Production of Filter for Hydrogen Production

[0166] Like in Example 2, a plurality of through holes were formed in aSUS304 member by etching using resist patterns as masks. However, afterthe etching process was finished, the resist patterns were not removed,but left on the surface of the SUS304 member. (hereinabove, the etchingprocess) Then, Ni strike plating (thickness: 0.2 μm) was applied underthe following condition to the inside of the through holes of theforegoing SUS304 member.

[0167] <Ni Strike Plating Condition> Bath composition: Nickel chloride300 g/L Boric acid  30 g/L pH: 2 Liquid temperature: 55 to 65° C.Current density: 10 A/dm²

[0168] Then, a Pd alloy film (thickness: 15 μm) was formed byelectrolytic plating under the following condition so as to close theinside of the through holes using the resist patterns as masks.(hereinabove, the film forming process)

[0169] <Film Forming Condition of Pd Alloy Film by Electrolytic Plating>

[0170] Using bath: Pd chloride plating bath (Pd concentration: 12 g/L)

[0171] pH: 7 to 8

[0172] Current density: 1 A/dm²

[0173] Liquid temperature: 40° C.

[0174] Then, the resist patterns on the SUS304 member were removed usinga 5% sodium hydroxide aqueous solution. (hereinabove, the removalprocess)

[0175] After the foregoing removal of the resist patterns was finished,cutting into a size of 3 cm×3 cm was carried out to obtain a filter forhydrogen production.

Evaluation of Hydrogen Production Filter

[0176] The filter thus produced was mounted in a reformer, and a mixtureof butane gas and steam was supplied to the Pd alloy film of the filterunder the same condition as Example 1, thereby to measure COconcentrations and flow rates of hydrogen rich gas transmitted to theside of the porous base member of the filter. As a result, the COconcentrations immediately after the start of reforming up to a lapse of300 hours were 8 to 10 ppm which were extremely low, and the flow ratesof the hydrogen rich gas were 10 L/hour, and therefore, it was confirmedthat the hydrogen production filter produced by the present inventionwas excellent in durability and hydrogen transmission efficiency.

COMPARATIVE EXAMPLE 2 Production of Filter for Hydrogen Production

[0177] Like in Example 2, a conductive base member was obtained byforming a plurality of through holes in a SUS304 member. Then, a Pdalloy film having a thickness of 30 μm was bonded to the conductive basemember via an adhesive so as to be unified together, and thereafter, theadhesive remaining in the through holes of the conductive base memberwas removed using acetone. This unified composite was cut into a size of3 cm×3 cm to obtain a filter for hydrogen production.

Evaluation of Hydrogen Production Filter

[0178] The filter thus produced was mounted in a reformer, and a mixtureof butane gas and steam was supplied to the Pd alloy film of the filterunder the same condition as Example 1, thereby to measure COconcentrations and flow rates of hydrogen rich gas transmitted to theside of the porous base member of the filter. As a result, the COconcentrations were 8 to 10 ppm, which were extremely low and thusexcellent, immediately after the start of reforming up to a lapse of 300hours. However, after the lapse of 300 hours, peeling of the Pd alloyfilm was caused due to degradation of the adhesive underhigh-temperature and high-pressure conditions, and the CO concentrationwas increased to about 3% due to generation of cracks of the Pd alloyfilm or the like, and therefore, it was confirmed that durability wasbad.

EXAMPLE 6 Production of Thin Film Support Substrate

[0179] A SUS304 member having a thickness of 150 μm was prepared as abase member, and a photosensitive resist material (OFPR manufactured byTokyo Ohka Kogyo Co., Ltd.) was applied (film thickness: 7 μm (upondrying)) to both surfaces of the SUS304 member by a dip method. Then, aphotomask having, in a pitch of 430 μm, a plurality of circular shadingportions each having a diameter of 390 μm was disposed on the resistapplication film on the side of the SUS304 member where columnar-convexportions are formed, and a photomask having, in a pitch of 430 μm, aplurality of circular opening portions each having an opening size(opening diameter) of 100 μm was disposed on the resist application filmon the opposite side. The resist application films were exposed via thephotomasks and developed using a sodium hydrogencarbonate solution. Bythis, circular resists each having the diameter of 390 μm were formed inthe pitch of 430 μm on one surface of the SUS304 member, while a resistpattern having the circular opening portions each having the openingsize (opening diameter) of 100 μm was formed on an opposite surface.Incidentally, positioning was carried out such that each vertex of atriangle having as its vertexes the centers of the nearestthree-circular resists (diameter: 390 μm) was located in a position ofthe center of gravity of a triangle having as its vertexes the centersof the nearest three opening portions of the resist pattern on theopposite side via the SUS304 member.

[0180] Then, the SUS304 member was etched under the following conditionusing the foregoing resist patterns as masks. This etching was forforming columnar convex portions by half etching from one surface of theSUS304 member, and simultaneously, forming through holes by etching fromboth surfaces, and a time required for the etching was six minutes.

[0181] <Etching Condition>

[0182] Temperature: 50° C.

[0183] Iron chloride concentration: 45 Baume

[0184] Pressure: 3 kg/cm²

[0185] After the foregoing etching process was finished, the resistpatterns were removed using a sodium hydroxide solution, and washing inwater was carried out. By this, a thin film support substrate-as shownin FIG. 5 was obtained, wherein the columnar convex portions of acylindrical shape having a diameter of 290 μm and a height of 60 μm wereformed in the pitch of 430 μm on one surface of the SUS304 member havinga thickness of 90 μm, and the through holes each having an openingdiameter of 70 to 100 μm were formed in the pitch of 430 μm in theSUS304 member at a portion where the columnar convex portions were notformed. In this thin film support substrate, an area of the columnarconvex portion non-formed portion occupying on the side where thecolumnar convex portions were formed, was about 50%.

Production of Filter for Hydrogen Production

[0186] On the surface of the thus produced thin film support substratewhere the columnar convex portions were formed, an insulating film(polyethylene terephthalate film) having a thickness of 200 μm was stuckto be disposed (hereinabove, the disposing process).

[0187] Then, the following pretreatment was applied to the thin filmsupport substrate excluding top surfaces of the columnar convex portions(including the inside of the through holes) and to the sticking side ofthe insulting film, and thereafter, electroless plating was performedunder the following condition to form an electroless nickel platinglayer (thickness: 0.4 μm), thereby obtaining a conductive underlayer.(hereinabove, the underlayer forming process)

[0188] <Pretreatment>

[0189] alkaline degreasing→washing in water→chemical etching (inammonium persulfate 200 g/L aqueous solution (20° C.±5° C.))→washing inwater→acid treatment (10% dilute sulfuric acid (ordinarytemperature))→washing in water→acid treatment (30% dilute hydrochloricacid (ordinary temperature))→dipping in sensitizer added liquid(composition: 0.5 g of Pd chloride, 25 g of stannous chloride, 300 μmLof hydrochloric acid, 600 μmL of water)→washing in water

[0190] <Electroless Nickel Plating Condition> Bath composition: Nickelsulfate 20 g/L Sodium hypophosphite 10 g/L Lactic acid  3 g/L Sodiumcitrate  5 g/L Sodium acetate  5 g/L pH: 4.5 to 6.0 Liquid temperature:50 to 65° C.

[0191] Then, electrolytic copper plating was applied to the conductiveunderlayer under the following condition to form a copper plating layerso as to fill up spaces formed between the columnar convex portionnon-formed surface of the thin film support substrate and the insulatingfilm, and the inside of the through holes of the thin film supportsubstrate. (hereinabove, the copper plating process)

[0192] <Copper Plating Condition>

[0193] Using bath: Copper sulfate plating bath

[0194] Liquid temperature: 30° C.

[0195] Current density: 1 A/dm²

[0196] Then, the insulating film was peeled and removed from the thinfilm support substrate, and a Pd alloy film (thickness: 3 μm) was formedby electrolytic plating on the thin film support substrate (top surfacesof the columnar convex portions) and the copper plating layer after theremoval under the following condition. Incidentally, upon thiselectrolytic plating, the copper plating layer on the back side of thethin film support substrate was covered with an insulating film.(hereinabove, the film forming process)

[0197] <Film Forming Condition of Pd Alloy Film by Electrolytic Plating>

[0198] Using bath: Pd chloride plating bath (Pd concentration: 12 g/L)

[0199] pH: 7 to 8

[0200] Current density: 1 A/dm²

[0201] Liquid temperature: 40° C.

[0202] Then, the insulating film was peeled and removed, and further,the copper plating layer was removed by selective etching. (hereinabove,the removal process) After the foregoing removal of the copper platinglayer was finished, cutting into a size of 3 cm×3 cm was carried out toobtain a filter for hydrogen production.

Evaluation of Hydrogen Production Filter

[0203] The hydrogen production filter thus produced was mounted in areformer, and a mixture of butane gas and steam was supplied to the Pdalloy film of the filter under the same condition as Example 1, therebyto measure CO concentrations and flow rates of hydrogen rich gastransmitted to the side of the porous base member of the filter. As aresult, the CO concentrations immediately after the start of reformingup to a lapse of 300 hours were 8 to 10 ppm which were extremely low,and the flow rates of the hydrogen rich gas were 10 L/hour, andtherefore, it was confirmed that the hydrogen production filter producedby the present invention was excellent in durability and hydrogentransmission efficiency.

EXAMPLE 7 Production of Thin Film Support Substrate

[0204] Like in Example 6, a thin film support substrate of the presentinvention was produced.

Production of Filter for Hydrogen Production

[0205] On the surface of the thus produced thin film support substratewhich is on the opposite side relative to the columnar convex portionformed side, an insulating film (polyethylene terephthalate film) havinga thickness of 200 μm was stuck to be disposed (hereinabove, thedisposing process).

[0206] Then, electrolytic copper plating was applied to the surface ofthe thin film support substrate on the columnar convex portion formedside to form a copper plating layer (thickness: about 80 μm) on the thinfilm support substrate so as to fill up the inside of the through holesand cover the columnar convex portions. The copper plating condition wasthe same as in Example 6. (hereinabove, the copper plating process)

[0207] Then, the copper plating layer was flat-removed by grinding so asto expose the top surfaces of the columnar convex portions and form thesame flat surface with the top surfaces. In this event, the groundsurface was smoothed as much as possible. (hereinabove, the flatteningprocess)

[0208] Then, a Pd alloy film (thickness: 3 μm) was formed on theforegoing flat surface. The electrolytic plating condition for this Pdalloy film was the same as in Example 6. (hereinabove, the film formingprocess)

[0209] Then, the insulating film was peeled and removed, and further,the copper plating layer was removed by selective etching. (hereinabove,the removal process)

[0210] After the foregoing removal of the copper plating layer wasfinished, cutting into a size of 3 cm×3 cm was carried out to obtain afilter for hydrogen production.

Evaluation of Hydrogen Production Filter

[0211] The hydrogen production filter thus produced was mounted in areformer, and a mixture of butane gas and steam was supplied to the Pdalloy film of the filter under the same condition as Example 1, therebyto measure CO concentrations and flow rates of hydrogen rich gastransmitted to the side of the porous base member of the filter. As aresult, the CO concentrations immediately after the start of reformingup to a lapse of 300 hours were 8 to 10 ppm which were extremely low,and the flow rates of the hydrogen rich gas were 10 L/hour, andtherefore, it was confirmed that the hydrogen production filter producedby the present invention was excellent in durability and hydrogentransmission efficiency.

EXAMPLE 8 Production of Thin Film Support Substrate

[0212] Like in Example 6, a thin film support substrate of the presentinvention was produced.

Production of Filter for Hydrogen Production

[0213] A resin layer was formed on the surface of the thus produced thinfilm support substrate on the columnar convex portion formed side, byfilling/applying a resin material (AZ1111 manufactured by ShipleyCorporation) by squeezing so as to fill up the inside of the throughholes and cover the columnar convex portions. (hereinabove, the resinlayer forming process)

[0214] Then, the resin layer was flat-removed by grinding so as toexpose the top surfaces of the columnar convex portions and form thesame flat surface with the top surfaces. In this event, the groundsurface was smoothed as much as possible. (hereinabove, the flatteningprocess)

[0215] Then, electroless plating was performed to form an electrolessnickel plating layer (thickness: 0.4 μm) on the foregoing flat surface,thereby to obtain a conductive underlayer. The condition of theelectroless nickel plating was the same as in Example 6. (hereinabove,the underlayer forming process)

[0216] Then, a Pd alloy film (thickness: 3 μm) was formed on theforegoing conductive underlayer. The electrolytic plating condition forthis Pd alloy film was the same as in Example 6. Upon the electrolyticplating, the opposite surface relative to the Pd alloy film formationwas coated with an insulating film. (hereinabove, the film formingprocess)

[0217] Then, the insulating film was peeled and removed, and further,the resin layer was dissolved to be removed using the followingtreatment bath (Desmear Bath manufactured by Shipley Corporation).(hereinabove, the removal process)

[0218] <Treatment Condition of Desmear Bath> Bath composition MLB-211 20vol % of swelling process: Cup-Z 10 vol % Bath temperature 80° C. ofswelling process: Bath composition of MLB-213A 10 vol % rougheningprocess: MLB-213B 15 vol % Bath temperature of 80° C. rougheningprocess:

[0219] After the foregoing removal of the resin layer was finished,cutting into a size of 3 cm×3 cm was carried out to obtain a filter forhydrogen production.

Evaluation of Hydrogen Production Filter

[0220] The hydrogen production filter thus produced was mounted in areformer, and a mixture of butane gas and steam was supplied to the Pdalloy film of the filter under the same condition as Example 1, therebyto measure CO concentrations and flow rates of hydrogen rich gastransmitted to the side of the porous base member of the filter. As aresult, the CO concentrations immediately after the start of reformingup to a lapse of 300 hours were 8 to 10 μm which were extremely low, andthe flow rates of the hydrogen rich gas were 10 L/hour, and therefore,it was confirmed that the hydrogen production filter produced by thepresent invention was excellent in durability and hydrogen transmissionefficiency.

EXAMPLE 9 Production of Thin Film Support Substrate

[0221] Like in Example 6, a thin film support substrate of the presentinvention was produced.

Production of Filter for Hydrogen Production

[0222] Ni strike plating (thickness: 0.01 μm) was applied to a copperbase member having a thickness of 0.2 mm under the following condition.

[0223] <Ni Strike Plating Condition> Bath composition: Nickel chloride300 g/L Boric acid  30 g/L pH: 2 Liquid temperature: 55 to 65° C.Current density: 10 A/dm²

[0224] Then, a Pd alloy film (thickness: 3 μm) was formed on one surfaceof the copper base member applied with the foregoing Ni strike plating.The electrolytic plating condition for this Pd alloy film was the sameas in Example 6. Upon the electrolytic plating, the opposite surfacerelative to the Pd alloy film formation was coated with an insulatingfilm. (hereinabove, the film forming process)

[0225] Then, after peeling and removing the insulating film from thecopper base member, the foregoing Pd alloy film was brought into contactwith the top surfaces of the columnar convex portions of the thin filmsupport substrate and, by applying a heat treatment at 1000° C. for 12hours in a vacuum, the Pd alloy film and the top surfaces of thecolumnar convex portions were joined together by diffusion to therebydispose the copper base member. (hereinabove, the diffusion joiningprocess)

[0226] Then, the copper base member was removed by selective etching.(hereinabove, the removal process)

[0227] After the foregoing removal of the copper base member wasfinished, cutting into a size of 3 cm×3 cm was carried out to obtain afilter for hydrogen production.

Evaluation of Hydrogen Production Filter

[0228] The hydrogen production filter thus produced was mounted in areformer, and a mixture of butane gas and steam was supplied to the Pdalloy film of the filter under the same condition as Example 1, therebyto measure CO concentrations and flow rates of hydrogen rich gastransmitted to the side of the porous base member of the filter. As aresult, the CO concentrations immediately after the start of reformingup to a lapse of 300 hours were 8 to 10 μm which were extremely low, andthe flow rates of the hydrogen rich gas were 10 L/hour, and therefore,it was confirmed that the hydrogen production filter produced by thepresent invention was excellent in durability and hydrogen transmissionefficiency.

Industrial Applicability

[0229] As described above, the production method of the hydrogenproduction filter according to the present invention is suitable forproducing a hydrogen production filter that is used in a reformer of afuel cell so as to be capable of stably producing high purity hydrogengas.

1. A production method of a hydrogen production filer, characterized bycomprising a through hole closing step of attaching a metal plate to onesurface of a conductive base member having a plurality of through holesby the use of a magnet, a copper plating step of forming a copperplating layer on the conductive base member and said metal plate exposedwithin the through holes, from the side of said conductive base memberwhere said metal plate is not attached, thereby to fill up said throughholes, a film forming step of forming a Pd alloy film by plating on thesurface of said conductive base member after removal of said metalplate, and a removal step of removing said copper plating layer byselective etching.
 2. A production method of a hydrogen production fileraccording to claim 1, wherein the Pd alloy film is formed byelectrolytic plating in said film forming step.
 3. A production methodof a hydrogen production filer according to claim 1, wherein, in saidfilm forming step, thin films of respective components composing a Pdalloy are first stacked in layers by plating, then a heat treatment isapplied thereto to form the Pd alloy film by diffusion of thecomponents.
 4. A production method of a hydrogen production fileraccording to claim 1, wherein said conductive base member is a ferritestainless substrate.
 5. A production method of a hydrogen productionfiler according to claim 1, wherein said metal plate is a ferritestainless substrate.
 6. A production method of a hydrogen productionfiler, characterized by comprising a sticking step of sticking aninsulating film to one surface of a conductive base member having aplurality of through holes, a copper plating step of forming a copperplating layer on a surface of said conductive base member where saidinsulating film is not stuck, so as to fill up said through holes, afilm forming step of forming a Pd alloy film by plating on the surfaceof the conductive base member after removal of said insulating film, anda removal step of removing said copper plating layer by selectiveetching.
 7. A production method of a hydrogen production filer accordingto claim 6, wherein the Pd alloy film is formed by electrolytic platingin said film forming step.
 8. A production method of a hydrogenproduction filer according to claim 6, wherein, in said film formingstep, thin films of respective components composing a Pd alloy are firststacked in layers by plating, then a heat treatment is applied theretoto form the Pd alloy film by diffusion of the components.
 9. Aproduction method of a hydrogen production filer according to claim 6,wherein said conductive base member is a stainless substrate.
 10. Aproduction method of a hydrogen production filer, characterized bycomprising a filling step of filling a resin material into through holesof a conductive base member having the plurality of through holes, anunderlayer forming step of forming a Pd alloy film on one surface ofsaid conductive base member by either of electroless plating and avacuum film forming method, thereby to form a conductive underlayer, afilm forming step of forming a Pd alloy film by plating on saidconductive underlayer, and a removal step of dissolving and removingonly said resin material.
 11. A production method of a hydrogenproduction filer according to claim 10, wherein the Pd alloy film isformed by electrolytic plating in said film forming step.
 12. Aproduction method of a hydrogen production filer according to claim 10,wherein, in said film forming step, thin films of respective componentscomposing a Pd alloy are first stacked in layers by plating, then a heattreatment is applied thereto to form the Pd alloy film by diffusion ofthe components.
 13. A production method of a hydrogen production fileraccording to claim 10, wherein said conductive base member is astainless substrate.
 14. A production method of a hydrogen productionfiler, characterized by comprising an etching step of formingpredetermined resist patterns on both surfaces of a conductive basemember, and etching said conductive base member from both sides usingsaid resist patterns as masks to form a plurality of through holes, afilm forming step of forming a Pd alloy film by electrolytic plating soas to close the inside of said through holes of said conductive basemember, and a removal step of removing said resist patterns.
 15. Aproduction method of a hydrogen production filer according to claim 14,wherein, in said film forming step, thin films of respective componentscomposing a Pd alloy are first stacked in layers by electrolyticplating, then a heat treatment is applied thereto to form the Pd alloyfilm by diffusion of the components.
 16. A production method of ahydrogen production filer according to claim 14, wherein said conductivebase member is a stainless substrate.
 17. A thin film support substratefor use in a hydrogen production filter, characterized by comprising ametal substrate, a plurality of columnar convex portions formed on onesurface of said metal substrate, and a plurality of through holes formedat a portion where said columnar convex portions are not formed, so asto pierce the metal substrate, wherein an area of the columnar convexportion non-formed portion occupying on the columnar convex portionformed side is within the range of 20 to 90%.
 18. A thin film supportsubstrate according to claim 17, wherein said columnar convex portionshave a diameter within the range of 20 to 500 μm, a formation pitchwithin the range of 40 to 700 μm, and a height within the range of 10 to200 μm.
 19. A thin film support substrate according to claim 17, whereinsaid through hole has an opening diameter within the range of 20 to 200μm.
 20. A thin film support substrate according to claim 17, whereinsaid metal substrate is an austenite or ferrite stainless substrate. 21.A thin film support substrate according to claim 17, wherein saidcolumnar convex portions are formed by half-etching said metalsubstrate, and said through holes are formed by etching said metalsubstrate from both surfaces.
 22. A production method of a hydrogenproduction filer using a thin film support substrate, characterized bycomprising a disposing step of disposing an insulating film on a surfaceof the thin film support substrate where columnar convex portions areformed, so as to fix said insulating film to top surfaces of saidcolumnar convex portions, said thin film support substrate comprising ametal substrate, the plurality of columnar convex portions formed on onesurface of said metal substrate, and a plurality of through holes formedat a portion where said columnar convex portions are not formed, so asto pierce said metal substrate, wherein an area of the columnar convexportion non-formed portion occupying on the columnar convex portionformed side is within the range of 20 to 90%, an underlayer forming stepof forming a conductive underlayer by electroless plating on said thinfilm support substrate excluding the top surfaces of said columnarconvex portions and on a fixation side of said insulating film, a copperplating step of forming a copper plating layer on said conductiveunderlayer so as to fill up a space formed between the metal substrateof said thin film support substrate and said insulating film, and theinside of the through holes of said thin film support substrate, a filmforming step of forming a Pd alloy film by plating on a surface formedby the top surfaces of said columnar convex portions and said copperplating layer after removal of said insulating film, and a removal stepof removing said copper plating layer by selective etching.
 23. Aproduction method of a hydrogen production filer according to claim 22,wherein the Pd alloy film is formed by electrolytic plating in said filmforming step.
 24. A production method of a hydrogen production fileraccording to claim 22, wherein, in said film forming step, thin films ofrespective components composing a Pd alloy are first stacked in layersby plating, then a heat treatment is applied thereto to form the Pdalloy film by diffusion of the components.
 25. A production method of ahydrogen production filer using a thin film support substrate,characterized by comprising a disposing step of disposing an insulatingfilm on a surface of the thin film support substrate which is on anopposite side relative to a surface where columnar convex portions areformed, said thin film support substrate comprising a metal substrate,the plurality of columnar convex portions formed on one surface of saidmetal substrate, and a plurality of through holes formed at a portionwhere said columnar convex portions are not formed, so as to pierce saidmetal substrate, wherein an area of the columnar convex portionnon-formed portion occupying on the columnar convex portion formed sideis within the range of 20 to 90%, a copper plating step of forming acopper plating layer on the surface of said thin film support substratewhere the columnar convex portions are formed, so as to fill up theinside of said through holes and cover said columnar convex portions, aflattening step of flat-removing said copper plating layer so as toexpose top surfaces of said columnar convex portions and form the sameflat surface with said top surfaces, a film forming step of forming a Pdalloy film by plating on the flat surface formed by the top surfaces ofsaid columnar convex portions and said copper plating layer, and aremoval step of removing the copper plating layer by selective etchingafter removal of said insulating film.
 26. A production method of ahydrogen production filer according to claim 25, wherein the Pd alloyfilm is formed by electrolytic plating in said film forming step.
 27. Aproduction method of a hydrogen production filer according to claim 25,wherein, in said film forming step, thin films of respective componentscomposing a Pd alloy are first stacked in layers by plating, then a heattreatment is applied thereto to form the Pd alloy film by diffusion ofthe components.
 28. A production method of a hydrogen production filerusing a thin film support substrate, characterized by comprising a resinlayer forming step of forming a resin layer on a surface of the thinfilm support substrate where columnar convex portions are formed, so asto fill up the inside of through holes of the thin film supportsubstrate and cover said columnar convex portions, said thin filmsupport substrate comprising a metal substrate, the plurality ofcolumnar convex portions formed on one surface of said metal substrate,and the plurality of through holes formed at a portion where saidcolumnar convex portions are not formed, so as to pierce said metalsubstrate, wherein an area of the columnar convex portion non-formedportion occupying on the columnar convex portion formed side is withinthe range of 20 to 90%, a flattening step of flat-removing said resinlayer so as to expose top surfaces of said columnar convex portions andform the same flat surface with said top surfaces, an underlayer formingstep of forming a conductive underlayer by either of electroless platingand a vacuum film forming method on the flat surface formed by the topsurfaces of said columnar convex portions and said resin layer, a filmforming step of forming a Pd alloy film by plating on said conductiveunderlayer, and a removal step of dissolving and removing only saidresin layer.
 29. A production method of a hydrogen production fileraccording to claim 28, wherein the Pd alloy film is formed byelectrolytic plating in said film forming step.
 30. A production methodof a hydrogen production filer according to claim 28, wherein, in saidfilm forming step, thin films of respective components composing a Pdalloy are first stacked in layers by plating, then a heat treatment isapplied thereto to form the Pd alloy film by diffusion of thecomponents.
 31. A production method of a hydrogen production filer usinga thin film support substrate, characterized by comprising a filmforming step of forming a Pd alloy film by plating on one surface of ametal base member that is capable of selective etching relative to thethin film support substrate comprising a metal substrate, a plurality ofcolumnar convex portions formed on one surface of said metal substrate,and a plurality of through holes formed at a portion where said columnarconvex portions are not formed, so as to pierce said metal substrate,wherein an area of the columnar convex portion non-formed portionoccupying on the columnar convex portion formed side is within the rangeof 20 to 90%, a diffusion joining step of disposing said metal basemember on a surface of said thin film support substrate where thecolumnar convex portions are formed, by diffusion joining said Pd alloyfilm to the top surfaces of the columnar convex portions, and a removalstep of removing said metal base member by selective etching.
 32. Aproduction method of a hydrogen production filer according to claim 31,wherein the Pd alloy film is formed by electrolytic plating in said filmforming step.
 33. A production method of a hydrogen production fileraccording to claim 31, wherein, in said film forming step, thin films ofrespective components composing a Pd alloy are first stacked in layersby plating, then a heat treatment is applied thereto to form the Pdalloy film by diffusion of the components.